TECHNOLOGY
FEATURE
Lubricant requirements
for hybrid vehicles
H
ybrid vehicles might account for only a small proportion of the global vehicle fleet but, as consumers look
for improved fuel economy, their popularity is growing. Insight reveals the findings of New York City field
trials, designed to assess the opportunities these vehicles present to lubricant marketers for specifically
tailored lubricants.
As part of their overall strategy to lower fuel consumption and reduce CO2 emissions to meet current or projected
requirements, OEMs have been looking at the electrification of the powertrain and other low emission technologies.
One option is hybrid-electric, where vehicles are driven by a conventional internal combustion engine and by
the power from the electrical system. Features of hybrid electric vehicles (HEV), such as regenerative braking or
stopping the engine during idle, can significantly improve fuel economy and lower CO2 emissions - making them
increasingly popular with OEMs.
Toyota has been the market leader in this segment for some time. But now a number of large manufacturers are
developing and launching HEVs because they see the technology as a good bridge until more advanced diesel and
electric vehicles are fully developed. However, the global uptake of HEVs is far from homogeneous, and OEMs still
have work to do to gain acceptance of hybrid technology by consumers in many regions.
Market round up
In the US for example, it has been a pretty good
year for the passenger vehicle market as a whole,
with total auto sales up over 4% for the first half of
2014. But a closer look reveals that while diesel,
plug in and battery sales are all up, hybrid sales
are down by almost 10% over the same period
last year.
In Europe it has also been a good first half of
the year, with total car sales growing by 6.2% reaching over 6.8 million vehicles. Toyota reports
sales in Europe of its hybrid models reached
75,623 units for the first half of the year. While
this is a 17% increase versus last year, it represents
just 1% of the European market.
China is the largest single-country car market
in the world, and in the first half of 2014 new
vehicle registrations were up 14.5% over the
same period last year. China has high green
transportation aspirations and to encourage
sales the government has exempted hybrid and
electric cars from its 10% purchase tax from
September 2014 to the end of 2017. But despite
these measures and increased availability, electric
and hybrid cars together represented just 0.2% of
the 11.7 million cars purchased during the first
half of this year.
Lubricant considerations
Although as a proportion of total new vehicle
registrations HEV sales are still relatively small,
every vehicle owner has the right to be sure
that the lubricant they put in their vehicle will
sufficiently protect the engine.
A distinguishing feature of HEVs is the
ability to turn off the conventional engine when
the power available from the electrical system
exceeds that required to propel the vehicle.
The engine-off feature saves fuel and engine
hours but also results in cooler operating
temperatures of the internal combustion engine
and increases engine stress through the more
frequent starts of the engine.
These distinct operating conditions prompted
Infineum to initiate a research project to
determine the lubrication requirements of
HEVs relative to non-hybrid vehicles. This
understanding will then be used to assess the
opportunities available to lubricant marketers
26
September 2015 • | Lubezine Magazine